motor choice

I currently have a 1806 2300 kv motor (https://www.amazon.com/dp/B08P5MYWMH/?tag=lstir-20). On the Simple Cub it says I need a 2212 1050 kv motor. Is there a way I can use my original motor for the cub?

I'm trying to find the right motor that could carry/fly 5kg of RC Plane. What I've looked into so far has all given me the 1000kV for 900gram plane. Can we use that?

Another noob question. Is there a link to a chart that gives a guide to prop size to KV value of the motor? I've picked up 4 x 600kv motors for my scratch build and I get that low kv = large prop/ more torque but I can't see what size props to use. Thanks. :)